But you gotta remember too, without doing anything to the scuba, its gonna sound the same. Ive had stock, straight pipe, and the trd. The trd I have on now and can barely tell except a 1500 rpm rumble. After that, nada. The straight pipe was the only dif, even that wasnt at all loud. Go ahead and take off your muffler. And drive around a little, youll see.